bio mass

1. BIOMASS ENERGY
UNIT 3

2. CONTENT
• Basic
• Sources of Biomass
• Thermo-chemical Process
• Bio-Chemical Process
• Pyrolysis, Gasification, Combustion , Fermentation
• Updraft, Downdraft
• Fixed and Floating digester Biogas plants
• Economics of Biomass power generation

3. BIOMASS ENERGY

4. BIOMASS ENERGY
• Plant and Animal material, Especially agriculture waste products, used as a source of fuel

5. BIOMASS ENERGY
• Biomass resources fall into three categories
• First Category is to burn the biomass directly and get the energy.
• In the second category, the biomass is converted into ethanol and methanol to be used as
liquid fuels in engines.
• The third category is to ferment the biomass anaerobically to obtain a gaseous fuel called
biogas
• Biomass in its traditional solid mass (wood and agriculture residue)
• Biomass in non traditional form (Converted into liquid fuels)
• Biomass means organic matter and photochemical approach to harness solar energy
means harnessing of solar energy by photosynthesis. Solar energy is stored in the form of
chemical energy.
• Solar energy → Photosynthesis → Biomass Energy → Generation

6. BIOMASS ENERGY

7. BIOMASS ENERGY
BIOFUELS
• Liquids : Methanol, Ethanol, Butanol, Biodiesel
• Gases : Methane, Hydrogen
BIOHEAT
• Wood burning
BIOELECTRICITY
• Combustion in Boiler to Turbine
• Microbial Fuel Cells (MFCs)

8. BIOMASS CONVERSION PROCESS
BIOLOGICAL CONVERSION
• Fermentation (methanol, ethanol, butanol)
• Anaerobic digestion (methane)
• Anaerobic respiration (bio-battery)
CHEMICAL CONVERSION
• Transesterification (biodiesel)
THERMAL CONVERSION
• Combustion
• Gasification
• Pyrolysis

9. BIOMASS ENERGY

10. BIOMASS ENERGY

11. BIOMASS ENERGY
• COMBUSTION : Direct combustion of biomass is the most common way of converting
biomass to energy – both heat and electricity. Compared to the gasification and pyrolysis
it is the simplest and most developed
• GASIFICATION : Gasification is a high – temperature (1200 – 1400 Degree Celsius) thermos
chemical conversion process but the process is used for production of gas, instead of
heat.
• PYROLYSIS : Thermal decomposition occurring in the absence of oxygen. We use pyrolysis
to produce a liquid fuel, bio-oil or pyrolysis oil

12. THERMOCHEMICAL CONVERSION
• Gasification : Take place by heating the biomass with limited oxygen to produce low
heating value gas or by reacting it with steam and oxygen at high pressure and
temperature to produce medium heating value gas
• Liquefaction : The later may be used as fuel directly or used in liquefaction by converting
it to methanol (Methyl alcohol CH3CH2OH) or it may be converted to high heating value
gas.

13. THERMOCHEMICAL CONVERSION

14. BIOCHEMICAL CONVERSION
ANAEROBIC DIGESTION :
• Anaerobic digestion involves the microbial digestion of biomass. An anaerobic is a micro
organism that can live and grow without air or oxygen by the decomposition of matter
containing it)
• The process take place at low temperature upto 65 degree Celsius, and requires a
moisture content of at least 80 percent
• It generates a gas consisting mostly of CO2 and Methane (CH4) with minimum impurities
such as hydrogen sulphide.

15. ANAEROBIC DIGESTION

16. BIOCHEMICAL CONVERSION
FERMENTATION :
• Fermentation is the breakdown of complex molecules in organic compound under the
influence of a ferment such as yeast, bacteria, enzymes, etc.
• Fermentation is a well established and widely used technology for the conversion of
grains and crops into ethanol.

17. DRY PROCESSES
PYROLYSIS :
• A wide range of energy rich fuels can be produced by roasting dry woody matter like
straw and wood chips
• The materials is fed into reactor vessel or retort in a pulverised or shredded form and
heated in the absence of air.
• As the temperature rises the cellulose and lignin breakdown to simpler substance which
are driven off leaving a char residue behind.
• This method has been used for centuries to produce charcoal.

18. GASIFICATION
• Pyrolysis of wet biomass produces fuel gas and very little liquid
• An alternative technique for maximum gas yields is to blow small quantities of air or
oxygen into reactor vessel and to increases the temperature to over 1000 degree Celsius.
• This causes part of the feed to burn . Fuel gas from air blow gasifiers has a low calorific
values and may contain upto 40% inert nitrogen gas overall yields of 80 -85% can be
expected.

19. STEAM GASIFICATION
• Methane is produced directly from woody matter by treatment at high temperature and
pressure with hydrogen gas.
• The hydrogen can be added or , more commonly , generated in the reactor vessel from
carbon monoxide and steam.
• Recent analysis suggest that steam gasification is the most efficient route to methanol
• Net energy yields 55% can be achieved although higher yields are likely in the future as
the technology is developed.

20. HYDROGENATION
• Under less severe condition of temperature and pressure (300 – 400 degree Celsius and
100 atmospheres), carbon monoxide and steam react with cellulose to produce heavy oils
which can be separated and refined to premium fuels

21. BIOMASS PROCESS

22. BIOGAS
• Getting energy out of biomass by burning it, turning it into a liquid or by turning it into a
gas called bio gas.
• It contains about 65 % of methane gas as a major constituents

23. BIOGAS
• Biogas contain 55 – 65 % methane , 30 -40 % CO2 , and the remainders are impurities like
H2S, H2, N2 gases.
• Cattle dung can produce 0.037 mcube of biogas per kg of cow dung. The calorific value of
gas is 21000 to 23000 kJ/kg or about 38000 kJ/mcube of gas. The material from which
biogas is produced retains its value as fertilizer or as animal feed which can be used after
certain processing
• Biogas can be produced by digestion pyrolysis or hydro gasification. Digestion is a
biological process that occurs in absence of O2 and in presence of anaerobic organisms at
atmospheric pressure in which the digestion takes place is called digester.
• When organic matter undergoes fermentation, the anaerobic bacteria extracts oxygen by
decomposing the biomass at low temperature upto 65 degree Celsius in the presence of
moisture (80 – 95 %) the gas so produced is called biogas.

24. PRINCIPLE OF BIOGAS PRODUCTION
• HYDROLYSIS : In this stage , matters with heavy molecular weight are disintegrated into
lower molecular weight. This process takes place by hydrolytic bacteria.
• ACID FORMATION : In this stage, organic matters are conversion takes place by acetates
and H2. This conversion takes places by acetogenes. Then H2 and C are converted into
acetate by acetogenes.
• METHANE GAS FORMATION : In this stage, acetates and simple CO2 are converted into
CH4 . This is carried out by methanogens.

25. BIOGAS

26. FACTORS AFFECTING BIOGAS
PRODUCTION
• Temperature & Pressure
• Solid concentration & Loading rate
• Retention period
• pH value
• Nutrients composition
• Toxic substances
• Digester size & shape
• Stirring agitation of the content of digestion.

27. BIOFUEL
• Biofuel is a bioorganic fuel. It is obtained by the fermentation of biomass
• The process by which micro-organisms break down complex organic substances generally
in the absence of oxygen to produce alcohol and carbon dioxide is called Fermentation.
EXAMPLE :
• ETHANOL : It is produced from sugarcane. Its CALORIFIC VALUE is less than petrol. It also
less heat when compare to petrol.
• METHANOL : It is easily obtained from ethanol. Its CALORIFIC VALUE is too low when
compared to gasoline and diesel
• GASOHOL : It is a mixture of ethanol + gasoline . It is used in cars and buses

28. BIOENERGY
SIGNIFICANCE OF BIO-
ENERGY
• Cost is low when compare
to fossil fuels
• Biomass consumes more
CO2 that is released during
combustion of biomass.

29. BIOFUEL VS FOSSIL FUEL
BIOFUEL : Biofuel is produced directly from plant matter typically corn, sugar cane, sugar
beets, or cellulose transforming it into alcohol
FOSSIL FUEL : Fossil fuels are produced by either the decomposition of plant or animal
matter over long periods of time under certain conditions such as high temperature and
pressure. Fossil fuels are coal , oil and natural gas

30. OPERATION
• Biomass is organic compounds
produced in natural processes
• These compounds are transported
to the biomass plant and burned to
heat water.
• Steam is produced at high pressure
and it moves a turbine and this
moves the generator to produce
electricity

31. SITE SELECTION
• DISTANCE : The distance between the plant and the site of gas consumption should be less
in order to achieve economy in pumping of gas and minimizing gas leakage.. For the plant
of capacity 2 cubic meter, the optimum distance is 10m.
• Minimum gradient for converting the gas a minimum gradient of 1% must be made
available for the line.
• OPEN SPACE : The sunlight should fall on the plant as temperature between 15 degree
Celsius is essential for gas generation at good rate.
• WATER TABLE : the plant is normally constructed underground for ease of charging the
feed and loading slurry require less labour.
• SEASONAL RUN OFF : proper care has to be taken to prevent the interfere of run off water
during monsoon
• DISTANCE FROM WELLS : the seepage of fermented slurry may pollute the well water .
Hence a minimum of 15m should be maintained from wells.
• SPACE REQUIREMENT : Sufficient space must be available for day to day operation and
maintenance . As a guide line 10 to 12 cubic meter is needed per cubic meter of the gas.

32. ECONOMICS OF BIOMASS ENERGY
JUSTIFICATIONS FOR BIO-ENERGY ASSESSMENT
• SHUTDOWN OF THE SUGAR INDUSTRY
• Unemployment
• Decreased sources of income
• Recent increase in sugar prices
• CURRENT WASTE MANAGEMENT
• Health impacts
• Environmental impacts
• HIGH ENERGY PRICES
• High cost of diesel import for electricity generation
• High cost of transportation fuels
• Dependent on external geo-political forces

33. ECONOMICS OF BIOMASS ENERGY
MISSION :
• Find if there is reliable biomass feedstock supply for long term production
• Highlight commercially viable biomass to energy conversion approach
• Outline strategy for public-private partnership to develop biomass to energy
• Attract commercially proven developers to consider investment
• Focus on liquid biofuel and electric power production
• Potential for value-added products

34. ECONOMICS OF BIOMASS ENERGY
CHALLENGES :
• ECONOMIES OF SCALE
• Modest biomass feedstock availability
• Biomass conversion technologies
• LAND USE COMPETITION
• information dissemination on sustainable alternatives
• Familiarity with current methods of production

35. ECONOMICS OF BIOMASS ENERGY
OPPORTUNITIES :
• ENVIRONMENTAL/HEALTH BENEFITS
• CO2 reduction
• Increased soil fertility
• Sanitary issues
• JOB PROVISION
• Existence of skilled labor force
• ENERGY SECURITY
• ECONOMIC
• Avoided investment cost: No need for additional landfill/waste management
alternatives
• Decreased expenditures on electricity
• Diversification of economic activities

36. BIOMASS ENERGY ASSESSMENT
OBJECTIVE :
• Financial and economic analysis of a potential Domestic Bio-Energy Programme to test its
commercially sustainability
METHODOLOGY :
• Resource assessment (supply and demand)
• Technology identification
• Evaluate economic and financial feasibility of technologies given the resource availability
TECHNOLOGY IDENTIFICATION :
•Direct contact with experts and manufacturers
•Literature reviews and existing expertise
ECONOMIC AND FINANCIAL FEASIBILITY :
• Utilize feedstock supply, conversion and market data elements to evaluate feasibility of
Domestic Bio-Energy Programme

37. BIOMASS ENERGY ASSESSMENT
FOLLOW UP:
BIO-ENERGY AS PART OF THE SUSTAINABLE ENERGY PLAN (SEP) :
•Legislation
•Social benefits
•Institutional capacity
•Power purchase agreements
•Investors workshop
PLANS FOR THE ASSESSMENT :
• Remainder of this week
• Preparation of preliminary assessment
• Stakeholder review and comment on draft
• Presentation of findings
• Initiative to facilitate development

38. ADVANTAGES
• It’s a renewable source of energy
• It’s a comparatively lesser pollution generating energy.
• Biomass energy helps in cleanliness in villages and cities
• There is tremendous potential to generate biogas energy
• Biomass energy is relatively cheaper and reliable
• It can be generated from every day human and animal wastes, Vegetable and agriculture
left-over etc.
• Growing biomass crops use up carbon dioxide and produces oxygen.

39. DISADVANTAGES
• Cost of construction of biogas plant is high, so only rich people can use it.
• Some people don’t like to cook food on biogas produced from sewage waste.
• Biogas plant requires space and produces dirty smell.
• It is difficult to store biogas in cylinders.
• Transportation of biogas through pipe over distance is difficult
• Crops which are used to produce biomass energy are seasonal and are not available over
whole year,

40. APPLICATION
• Waste organic biomass can be directly used as domestic fuels.
• Biogas is used as domestic fuels in gas stoves like LPG
• Biogas can be used to run the engines , boilers and turbines
• Methane gas produced from biogas plants can be used to run the gas engines and farm
machineries
• It is used for heating the water.

41. CONCLUSIONS
• Biomass plants seem a good choice because they help clean up the waste that we produce
and are relatively cheap and safe, but their construction is very expensive, so only rich
people can use them
• They are also power generators that pollute comparatively less , but require much space
and produce odour.

42. THANK YOU